1. Field of the Invention
The present invention relates to a casing for an electronic component, said casing being "hardened" with respect to radiations, particularly ionizing radiations, that is to say a casing which protects the component which it contains against these radiations.
In the following description, for the sake of simplicity the term "component" will designate any discrete component or assembly of components forming an hybrid circuit or an integrated circuit, capable of being embedded in a casing.
2. Description of the Prior Art
The construction of high efficiency electronic equipment not only in so far as the processing speed but also the capacity or compactness are concerned, such as embarked computers, requires complex, high speed circuits with a high degree of integration of the LSI (Large Scale Integration) or VLSI (Very Large Scale Integration) type. However, these circuits are very sensitive to the effects of radiation, more particularly to those which result from ionization.
To limit these effects, two protection or hardening techniques are usually used. The first consists in forming an outer shrouding of the complete equipment, by means for example of sheets of suitably chosen metal. Its disadvantages are principally the weight and space required, particularly troublesome for embarked equipment. According to the second technique, for constructing the equipment components and/or circuits are chosen withstanding the radiations; such components and circuits exist at the present time but only in a small number and hardening thereof is the result both of the designing rules (taking more especially into account of the parameter variations and the damage caused by the radiations) and of the chosen technologies. However, these circuits are not efficient enough for some applications, more especially with regard to the degrees of integration reached; in addition, construction thereof according to hardened technology requires sometimes extremely long times; finally, the cost thereof is very high.